A: Ezekiel is called “son of man” 93 times in the book of Ezekiel. Apart from Jesus, only Ezekiel and Daniel (once: Dan 8:17) are called “son of man” in the Bible. Why did God use this term when speaking to Ezekiel? While it is impossible to know for sure, one primary reason is fairly prominent amongst scholars, and that is that God was stressing Ezekiel’s humanity.
Ezekiel was receiving powerful revelations directly from God, and perhaps God called Ezekiel “son of man” to keep him humble (much like He later humbled Paul with his “thorn in the flesh” in 2 Cor 12:7-10). It is worth noting that the Hebrew word used for “man” in Ezekiel (as in “son of man”) is “adam.” In pointing out that Ezekiel was the “son of man (adam),” perhaps He was pointing out his frailty, morality, lowliness, and weakness as a “human being” from below (the earth, descended from Adam), as contrasted with the deity of God, who was from above (Ps 8:4 and Job 25:6 sum this up nicely).
When we look at why Jesus called Himself the “son of man,” the view that God was stressing Ezekiel’s humanity is somewhat reinforced. Jesus called Himself the “Son Of Man” for two primary reasons: 1. To show that He was “fully” man, 2. To show that He was the Messiah that was prophesied in the book of Daniel (See: Dan 7:13-14) (He pointed to this in: Mt 24:30, Mt 26:64, Mk 13:26, Mk 14:62, Lk 21:27). Focusing on #1, while on earth, Jesus was fully God AND fully man (sometimes called the “hypostatic union“). In calling Himself the “Son Of God,” Jesus was stressing His deity, and in calling Himself the “Son Of Man,” Jesus was stressing His humanity. As we see in a number of Bible verses, this was very important (1 Jn 4:2-3)(2 Jn 1:7)(Heb 2:14)(Jn 1:14)(Rom 1:3-4).
Based on these things, I believe God was simply stressing Ezekiel’s humanity as a way to keep him humble.